LOS ANGELES (AP) — Three people including a Los Angeles police officer and a firefighter were hospitalized after being exposed to what was thought to be a dangerous substance.

Police Lt. Sabrina Kuhn tells City News Service that firefighters responded late Monday to a call of a possible overdose in Van Nuys.

They found a 23-year-old man had injected himself with a mix of an unknown white power and crushed castor beans. The deadly poison ricin is found in castor beans.

A HazMat team determined that the crushed castor beans were not harmful, but admitted the firefighter and officer to a hospital as a precautionary measure. Ten residences in the area were briefly evacuated.

No charges are pending against the initial subject of the call. Kuhn says he may be subject to mental evaluation upon release from the hospital.